I'm not sure how much of this needs to be true for the exploit to work, but when I have:
Spirit of Creation in diamond slot
Spirit of Order in ruby slot
Spirit of aestheticism in jade slot.
Then I can export the save and then purchase buildings. Then if I import that save, without closing the game first, I'll have the cookies I got before the purchase, and the buildings I got after the purchase, effectively letting me buy buildings for free (assuming I already have enough cookies for them).
I'm not sure if it matters, but I do use cookie monster, however I did try using this export without using cookie monster and it worked (that said, I didn't abandon my save so I still had the Third Party shadow achievement).
If purchasing the buildings unlocks an achievement or access to an upgrade then you'll still have that after the import.